package com.hnjowe.util;

import java.awt.image.BufferedImage;
import java.io.IOException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.output.ByteArrayOutputStream;

import com.octo.captcha.service.CaptchaServiceException;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;

/**
 * @图片验证码
 * @projectname：cocotour
 * @packagename：com.hnjowe.util
 * @filename：ImageCaptchaServlet.java
 * @date：2011-3-21 下午02:26:49
 * @author: wangxiuwu
 */
public class ImageCaptchaServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	public void init(ServletConfig servletConfig) throws ServletException {
        super.init(servletConfig);
    }

    protected void doGet(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws ServletException, IOException {
        
       byte[] captchaChallengeAsJpeg = null;
       // the output stream to render the captcha image as jpeg into
        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
        try {
        // get the session id that will identify the generated captcha. 
        //the same id must be used to validate the response, the session id is a good candidate!
        String loginType = httpServletRequest.getParameter("loginType");
        String captchaId = httpServletRequest.getSession().getId();
        // call the ImageCaptchaService getChallenge method
        BufferedImage challenge;
        if("store".equals(loginType)){
            challenge = ImageCaptchaServiceSingleton.getInstanceStore().getImageChallengeForID(captchaId,
                    httpServletRequest.getLocale());
        }else{
            challenge = ImageCaptchaServiceSingleton.getInstance().getImageChallengeForID(captchaId,
                    httpServletRequest.getLocale());
        }
            
            // a jpeg encoder
            JPEGImageEncoder jpegEncoder =
                    JPEGCodec.createJPEGEncoder(jpegOutputStream);
            jpegEncoder.encode(challenge);
        } catch (IllegalArgumentException e) {
            httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        } catch (CaptchaServiceException e) {
            httpServletResponse.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            return;
        }

        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();

        // flush it in the response
        httpServletResponse.setHeader("Cache-Control", "no-store");
        httpServletResponse.setHeader("Pragma", "no-cache");
        httpServletResponse.setDateHeader("Expires", 0);
        httpServletResponse.setContentType("image/jpeg");
        ServletOutputStream responseOutputStream =
                httpServletResponse.getOutputStream();
        responseOutputStream.write(captchaChallengeAsJpeg);
        responseOutputStream.flush();
        responseOutputStream.close();
    }


}
